Gum rosin is made of natural resin&comma; its general formula is C20H30O2&period;

Gum rosin also called colophony&comma; is a solid form of resin obtained from pines and some other plants&comma; mostly conifers&comma; produced by heating fresh liquid resin to vaporize the volatile liquid terpene components&period; It is semi-transparent and varies in color from yellow to black&period; At room temperature rosin is brittle&comma; but it melts at stove-top temperatures&period; It chiefly consists of different resin acids&comma; especially abietic acid&period;

Gum rosin is an important raw material for the manufacture of adhesive&comma; coating&comma; inks&comma; rubber&comma; soaps&comma; paper etc&period;